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@schollz
Created October 29, 2015 12:10
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Setup USB drive

First find the disk using

sudo fdisk -l

Its probably named /sda1 or similar. Then make ext4 using

sudo mkfs.ext4 /dev/sda1

To mount the drive use (e.g. mounting at /c)

sudo mkdir /c sudo mount /dev/sda1 /c sudo chgrp -R users /c sudo chmod -R g+w /c

Setup automount

sudo vim /etc/fstab

Add

/dev/sda1	/c	ext4	defaults	0	2

Get fail2ban

sudo apt-get install fail2ban 

Setup firewalls [source]

sudo nano /etc/iptables.firewall.rules

Add these basic rules:

*filter

#  Allow all loopback (lo0) traffic and drop all traffic to 127/8 that doesn't use lo0
-A INPUT -i lo -j ACCEPT
-A INPUT -d 127.0.0.0/8 -j REJECT

#  Accept all established inbound connections
-A INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT

#  Allow all outbound traffic - you can modify this to only allow certain traffic
-A OUTPUT -j ACCEPT

#  Allow HTTP and HTTPS connections from anywhere (the normal ports for websites and SSL).
-A INPUT -p tcp --dport 80 -j ACCEPT
-A INPUT -p tcp --dport 8888 -j ACCEPT
-A INPUT -p tcp --dport 443 -j ACCEPT

#  Allow SSH connections
#
#  The -dport number should be the same port number you set in sshd_config
#
-A INPUT -p tcp -m state --state NEW --dport 22 -j ACCEPT

#  Allow ping
-A INPUT -p icmp -j ACCEPT

#  Log iptables denied calls
-A INPUT -m limit --limit 5/min -j LOG --log-prefix "iptables denied: " --log-level 7

#  Drop all other inbound - default deny unless explicitly allowed policy
-A INPUT -j DROP
-A FORWARD -j DROP

COMMIT

Activate via:

sudo iptables-restore < /etc/iptables.firewall.rules

And check:

sudo iptables -L

Now setup auto activation by making file:

sudo nano /etc/network/if-pre-up.d/firewall

And adding:

#!/bin/sh 
/sbin/iptables-restore < /etc/iptables.firewall.rules

And make it executable:

sudo chmod +x /etc/network/if-pre-up.d/firewall
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